Unless there is evidence or experiences of harassments in your life, I would not worry about it.
If you wish you can always say a prayer of renunciation. At the blank lines you can include this spitting incident and anything else you wish:
Renunciation Of Satan and Claiming the Full Victory
I claim the full victory that my Lord Jesus Christ won on the Cross for me. Having disarmed the powers and authorities, He made a public spectacle of them, triumphing over them by the cross” (Col. 2:15). His victory for my is my victory.
In the name of the Lord Jesus Christ I renounce all the workings of Satan in my life in all its forms, whether brought into my life by my actions or by others,e, especially ______, ______, _____. I break all attachments, ground, curses, spells, and rights Satan may have in my life whether such ground was gained through my actions or through others. Strengthened by the intercession of the Immaculate Virgin Mary, Mother of God, of Blessed Michael the Archangel, of the Blessed Apostles Peter and Paul, and all the Saints and Angels of Heaven, and powerful in the holy authority of the name of the Lord Jesus Christ, I ask you Lord to command Satan and all his minions, whomever they may be, to get out of my life and stay out. With that authority I now take back the ground in my life gained by Satan through my sins. I reclaim this ground and my life for Christ. I now dedicate myself to the Lord Jesus Christ; I belong to Him alone. Amen.
Holy Michael the Archangel, defend us in battle. Be our protection against the wickedness and snares of the devil. May God rebuke him, we humbly pray; and do thou, O prince of the heavenly hosts, by the power of God, thrust into hell Satan and all the other evil spirits who prowl through the world seeking the ruin of souls. Amen.